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The Lucanian settlement of Caselle in Pittari represents one of the most interesting and amazing archaeological sites located in the Southern Italy. The excavations realized in the last three decades have confirmed the presence of an important settlement including houses, workshops, fortification walls. With the aim to identify the urban plan of the site, an extensive geophysical campaign was carried out in the last two years. Results show how the integrated use of archaeological information and geophysical data allow to reconstruct the ancient urban plan of the site formed by orthogonal roads (plateiai and stenopoi) that neatly delimit the isolates (insulae).

The M(w) 6.3, 2009 earthquake (L'Aquila, central Italy) was characterized by discontinuous surface rupture along the 19-km long NW-SE trending Paganica-San Demetrio fault system. The earthquake nucleated just below the town of L'Aquila at a depth of ca. 9 km, rupturing mainly toward SE. Due to the high urbanization of the area and to centuries-long agricultural works, the surficial traces of this fault system are not clear everywhere. In order to provide more detailed and accurate information concerning the Paganica fault segment, four Electrical Resistivity Tomographies (ERT) were carried out around the Paganica village area. ERT results were supported by interpretation of aerial photos, morphotectonic investigation, geological field survey, borehole data and a paleoseismological trench. The electrical images showed the cumulated offset of the fault at depth and the existence of other splays parallel to the main strand which depict a staircase geometry of the fault in the Paganica area.

A multidisciplinary approach based on the integration of in situ geophysical and geological techniques was applied to investigate the Orvieto Cathedral (Umbria Region, Central Italy) and the subsurface. In particular, the electrical resistivity tomography and the horizontal to vertical spectral ratio analysis of single station ambient vibrations measurements were used. This paper reports the results obtained with the joint analysis of the in situ geophysical investigations, geological field survey and borehole data. The joint analysis of different data allowed us (1) to image the geological setting, (2) to highlight some resonance frequencies of the monumental building, and (3) to estimate the resonance frequency of the site.

This paper deals with a geophysical survey carried out in some critical urban areas of the historical city of Matera (Southern Italy). Matera has a very complex shallower stratigraphy characterized by both anthropic and natural “targets” and is affected by geological instability. Therefore, Matera represents an ideal and very challenging outdoor laboratory for testing novel approaches for near-surface explorations in urban areas. Here, we present the results of a near-surface survey carried out by jointly applying Ground Penetrating Radar (GPR) and Electrical Resistivity Tomography (ERT) methods. The survey was implemented in three different critical zones within the urban area of Matera (Piazza Duomo, Piazza San Giovanni, Villa dell’Unità d’Italia). These test sites are of great interest for archaeological and architectonical studies and are affected by ground instability phenomena due to the presence of voids, cavities and other anthropic structures. The effectiveness of the survey was enhanced by the exploitation of advanced 3D tomographic approaches, which allowed to achieve 3D representation of the investigated underground and obtain information in terms of both the location and the geometry of buried objects and structures and the characterization of shallow geological layers. The results of the surveys are now under study (or have attracted the interest) of the Municipality in order to support smart cities programs and activities for a better management of the underground space.

The time and space anomalous behaviour of the Self-Potential (SP) field recorded in a seismic area of Southern Apennines, Italy, is discussed. The SP data were collected in the period June 1992-November 1994 along a profile located north of the town of Potenza in the Basilicata region, Italy. The profile is perpendicular to an active fault system, where a W-E directed strike-slip structure has been identified from recent earthquakes. The SP data are modelled using a new tomographic method based on the search for similarities between the observed SP sequence and the surface signature of the electric field due to a scanning point source with unitary positive charge. The point scanner is ideally moved in a vertical cross-section through the profile and a regular 2D matrix of charge occurrence probability values is thus obtained. These values are used to image the state of electric polarization in the subsoil, compatible with the observed SP surface pattern. A selection of 2D tomographies across the profile is then discussed in order to outline the SP source geometry and dynamics within the faulted structure. Finally, the time pattern of the SP polarization state is compared with the local seismicity in the frame of the rock dilatancy-fluid diffusion theory. This comparison allows us to exclude a direct relationship of the SP time behaviour with the seismic sequences which occurred in the area during the SP monitoring period.

The time dynamics of geoelectrical precursory time series has been investigated and a method to discriminate chaotic behaviour in geoelectrical precursory time series is proposed. It allows us to detect low-dimensional chaos when the only information about the time series comes from the time series themselves. The short-term predictability of these time series is evaluated using two possible forecasting approaches: global autoregressive approximation and local autoregressive approximation. The first views the data as a realization of a linear stochastic process, whereas the second considers the data points as a realization of a deterministic process, supposedly non-linear. The comparison of the predictive skill of the two techniques is a test to discriminate between low-dimensional chaos and random dynamics. The analyzed time series are geoelectrical measurements recorded by an automatic station located in Tito (Southern Italy) in one of the most seismic areas of the Mediterranean region. Our findings are that the global (linear) approach is superior to the local one and the physical system governing the phenomena of electrical nature is characterized by a large number of degrees of freedom. Power spectra of the filtered time series follow a P(f) = F-a scaling law: they exhibit the typical behaviour of a broad class of fractal stochastic processes and they are a signature of the self-organized systems.